ADOPTED LEVELS for 234Cm
Author: S. Ota | Citation: Nucl. Data Sheets 207, 351 (2026) | Cutoff date: 1-Dec-2023
Full ENSDF file | Adopted Levels (PDF version)
| Q(β-)=-6673 keV SY | S(n)= 8.64×103 keV 8 | S(p)= 3851 keV SY | Q(α)= 7365 keV 9 | ||
| Reference: 2021WA16 |
| E(level) (keV) | T1/2(level) |
| X | 53 s +9-7 % α ≈ 74 % ε ≈ 22 % SF ≈ 4 |
Additional Level Data and Comments:
| E(level) | Jπ(level) | T1/2(level) | Comments |
| X | 53 s +9-7 % α ≈ 74 % ε ≈ 22 % SF ≈ 4 | %α, %SF, and %ε+%β+ deduced by the evaluator from T1/2=53 s, T1/2(ε+β+)=240 s (theory, 1973Ta30 or 138 s (1975KoYO)), and T1/2(SF)≈1500 s (2002CaZZ). α more recent theory (2019Mo01) suggests T1/2(ε+β+)=38.85 s, which is shorter than the reported T1/2, therefore the evaluator did not consider the theoretical value here. Others: %α=71, %ε+%β+=27, and %SF=2 (2010Kh06), note the evaluator considers 2010Kh06 mistakenly and conversely presented %α=27 and %ε+%β+=71, since these were probably calculated assuming T1/2=51 s, T1/2(ε+β+)=240 s, and T1/2(SF)≈1500 s as listed in 2002CaZZ. %α≈40, %ε+%β+≈20, and %SF≈40, when using %α/%SF=0.94 9 (tentatively attributed to 238Cm by 2002CaZZ), T1/2=51 s, and T1/2(ε+β+)=240 s, as described in 2002CaZZ. %α=70, %ε+%β+=17, and %SF=13, when using T1/2=70 s, their partial cross sections for α and SF decay channels = 510 pb 230 and 96 pb 53 (2007KhZQ), and T1/2(ε+β+)=240 s (theory). E(level): %α, %SF, and %ε+%β+ deduced by the evaluator from T1/2=53 s, T1/2(ε+β+)=240 s (theory, 1973Ta30 or 138 s (1975KoYO)), and T1/2(SF)≈1500 s (2002CaZZ). α more recent theory (2019Mo01) suggests T1/2(ε+β+)=38.85 s, which is shorter than the reported T1/2, therefore the evaluator did not consider the theoretical value here. Others: %α=71, %ε+%β+=27, and %SF=2 (2010Kh06), note the evaluator considers 2010Kh06 mistakenly and conversely presented %α=27 and %ε+%β+=71, since these were probably calculated assuming T1/2=51 s, T1/2(ε+β+)=240 s, and T1/2(SF)≈1500 s as listed in 2002CaZZ. %α≈40, %ε+%β+≈20, and %SF≈40, when using %α/%SF=0.94 9 (tentatively attributed to 238Cm by 2002CaZZ), T1/2=51 s, and T1/2(ε+β+)=240 s, as described in 2002CaZZ. %α=70, %ε+%β+=17, and %SF=13, when using T1/2=70 s, their partial cross sections for α and SF decay channels = 510 pb 230 and 96 pb 53 (2007KhZQ), and T1/2(ε+β+)=240 s (theory). |
2016Ka13: 234Cm was produced from 234Bk(β+/ε) following 197Au(40Ar,3n)234Bk reaction. 40Ar beam, E=189.5 MeV, was delivered by the RIKEN heavy ion linear accelerator. Recoil products of interest (234Bk) were separated by RIKEN’s gas-filled recoil ion separator (GARIS), guided to a gas-jet chamber, stopped in helium gas and attached to KCL aerosols, collected and transported by a rotating wheel system to a position between seven pairs of Si PIN-diode detectors for α/SF spectroscopy. 234Cm were considered to be produced via 234Bk(β+/ε) rather than 197Au(40Ar,p3n) because of the latter’s small cross sections. Measured 17 α from the 234Bk (β+/ε)->234Cm decay chain via α - α correlations with daughter nuclides. Observed a dominant (85% intensity) 7.24 MeV 2 α line and a tentative, weak (15%) 7.14 MeV 2 α-line. T1/2 of the dominant line was measured to be 49 s +15-9. 2010KaZV is an earlier report by the same group.
2007KhZQ: Neutron deficient Cm isotopes were produced at SHIP using the fusion-evaporation reaction 208Pb(30Si,4n)234Cm. The 30Si beam with a charge state 6+ was prepared from 30SiO (99.5%), at the High Charge State Injector. α 5.27·A MeV beam was used to produce 234Cm. The 208PbS target with an average thickness of 412 μg/cm2 was irradiated for about one day. The identification of the Cm isotopes was made by using the α - α correlation method. 7.24 MeV 2 α events from 234Cm were observed and four spontaneous fission events (possibly from 234Cm) were also observed. The partial cross sections for α decay and spontaneous fission were 510 pb 230 and for 96 pb 53, respectively.
2002CaZZ: Activity produced by 198Pt(40Ar,4n) E=184-208 MeV. 95.7% isotopically enriched target. The measurement was performed at SHIP, GSI. 234Cm was identified by α - α correlations with daughter nuclides of the α-decay chain. Measured Eα=7239 keV 10 for the first time.
Q-value: ΔQ(β-)=154, ΔS(p)=115 (2021Wa16)
Q-value: S(2n)=15753 syst 202, S(2p)=6216 24 (2021Wa16)